Effects of high-temperature annealing on the microstructures and mechanical properties of C/C-ZrC-SiC composites prepared by precursor infiltration and pyrolysis
Effects of high-temperature annealing on the microstructures and mechanical properties of C/C-ZrC-SiC composites prepared by precursor infiltration and pyrolysis
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DOI：
10.1016/j.matdes.2015.10.140
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发表时间：
2016-01-15
影响因子：
8.4
通讯作者：
Zhang, Maoyan
中科院分区：
文献类型：
--
作者：
Ma, Chunhong;Guo, Lingjun;Zhang, Maoyan
采用前驱体浸渍-热解(PIP)工艺制备了C/C-ZrC-SiC复合材料。选择有机含锆聚合物和聚碳硅烷的混合溶液作为前驱体。将多孔碳/碳(C/C)预制体在真空下浸渍于前驱体中，在80℃下干燥，然后在1500℃下热解，经过20个循环的PIP工艺，获得了C/C-ZRC-SiC复合材料。复合材料在Ar气氛中分别在1650℃和1800℃下进一步处理2小时。研究了高温退火热处理对C/C-ZrC-SiC复合材料组织和性能的影响。结果表明，随退火温度的升高，密度逐渐减小，不同陶瓷相逐渐析出。复合材料在1650℃退火后，力学强度略有下降，在1800℃下，与未退火的复合材料相比，下降趋势更为明显。复合材料的断裂行为在热处理后发生了变化。强度的下降和力学性能的变化是由于退火引起的微结构变化引起的，包括气孔、裂纹、纤维损伤、弱界面结合和陶瓷相分离。(C)2015爱思唯尔有限公司。保留所有权利。
C/C-ZrC-SiC composites were fabricated by precursor infiltration and pyrolysis (PIP) process. A mixture solution of organic zirconium-containing polymer and polycarbosilane was chosen as the precursor. The porous carbon/carbon (C/C) preforms were first infiltrated in the precursor under vacuum, dried under 80 degrees C and then pyrolyzed at 1500 degrees C. After 20 cycles of PIP process, C/C-ZrC-SiC composites were obtained. The composites were further treated at 1650 degrees C and 1800 degrees C at an argon atmosphere for 2 h, respectively. The effects of high-temperature annealing on the microstructures and mechanical properties of C/C-ZrC-SiC composites were investigated. Results show that the density decreases and the different ceramic phases of the matrix get separated gradually as the annealing temperature increases. The mechanical strength decreases slightly after annealed at 1650 degrees C,and the downward trend is more obvious under 1800 degrees C in comparison to the unannealed composites. The fracture behavior of the composites changes after heat treatment. The decline of the strength and the change of the mechanical behaviors are attributed to the microstructural changes which include pores, cracks, fiber damage, weak interfacial bonding and ceramic phase separation caused by the annealing. (C) 2015 Elsevier Ltd. All rights reserved.